Hans Rosling, TED presenter and stats man extraordinaire shows that the best presenters do not need projectors and screens. They simply need a good idea and a creative way to present it. Of course it helps if you're charismatic and smart as hell.
In fact, by the time he moves to the projector and screen, he seems to disconnect with the audience because he's largely facing away from the audience. That's not to say Rosling talking with a screen is bad. But it is at that point the talk becomes more about content than delivery, and I refuse to believe either is better, but simply different.
It DOESN'T MATTER what he talks about - I'm engrossed. A great example of delivery matters as much or more than content, but, in this case, where the content is also relevant and interesting.